Some of the definitions used in 1960 differ from those used in 1950. These changes were made after consultation with users of census data in order to improve the statistics, even though it was recognized that comparability would be affected. The definitions and explanations should be interpreted in the context of the 1960 Censuses, in which data were collected by a combination of self-enumeration, direct interview, and observation by the enumerator.

The definitions below are consistent with the instructions given to the enumerator. As in all surveys, there were some failures to execute the instructions exactly. Through the forms distributed to households, the respondents were given explanations of some of the questions more uniformly than would have been given in direct interviews. Nevertheless, it was not feasible to give the full instructions to the respondents, and some erroneous replies have undoubtedly gone undetected.

More complete discussions of the definitions of population and housing items are given in 1960 Census of Population, Volume I, Characteristics of the Population. Part 1, United States Summary, and each of the State parts, and in 1960 Census of Housing, Volume I, States and Small Areas.

On the basis of census returns on several items, including household relationship, marital status, age, and sex, the population in households is classified into several categories according to family status. Within households, persons who are family members are distinguished from those who are not family members. Persons in families are subdivided into those who are related to the household head (that is, persons in "primary families") and all others (persons in "secondary families"). Family members are further classified by relationship to the family head. Persons in households, who are not family members, are subdivided into those who are household heads (primary individuals) and those who are not household heads (secondary individuals). The complexity of this classification is a reflection of the variety of family living arrangements which characterize the population.

A household consists of all the persons who occupy a housing unit. A house, an apartment or other group of rooms, or a single room, is regarded as a housing unit when it is occupied or intended for occupancy as separate living quarters; that is, when the occupants do not live and eat with any other persons in the structure and there is either (1) direct access from the outside or through a common hall or (2) a kitchen or cooking equipment for the exclusive use of the occupants.

All persons who are not members of households are regarded as living in group quarters; that is, in living quarters for institutional inmates or for other groups containing five or more persons unrelated to the person in charge. Most of the persons in group quarters live in rooming houses, college dormitories, military barracks, or institutions. The present report excludes persons in group quarters, a very small number of whom may have had relatives present. In the 1960 Census, persons in group quarters were sampled on an individual basis, and no information on family relationship was obtained for them.

A family consists of two or more persons in the same household who are related to each other by blood, marriage, or adoption; all persons living together in one household who are related to each other are regarded as one family. For example, if the son of the head of the household and the son's wife are members of the household, they are treated as part of the head's family. A lodger and his wife who are not related to the head of the household, or a resident employee and his wife living in, are considered as a separate family, however. Thus, a household may contain more than one family. A household head living alone or with nonrelatives only is not regarded as a family. Some households, therefore, do not contain a family.

A "primary family" comprises the head of a household and all (one or more) other persons in the household related to the head. All other families are "secondary families"; these comprise groups of mutually related persons, such as lodgers or resident employees.

The delineation of families is based on the relationship reported, among persons who were usual residents of a housing unit at the time of the enumeration. For instance, college students were enumerated at the place where they lived while attending college, and persons living in military establishments were enumerated where they were stationed. Such persons were not included in the statistics for their parental homes, even though they may have intended to return home on their completion of college or period of service.

A subfamily is a married couple with or without children, or one parent with one or more own single children under 18 years old, living in a household and related to, but not including, the head of the household or his wife. The most common example' of a subfamily is a young married couple sharing the home of the husband's or wife's parents. Only those single sons and daughters under 18 years old of a subfamily head are regarded as children in the subfamily. Members of a subfamily are also members of a primary family. The number of subfamilies, therefore, is not included in the number of families.

A primary individual is a head of a household who is living entirely alone or with one or more persons none of whom is related to him.
Type of household, family, or subfamily
The classification of households, families, and subfamilies by type is based on the sex and marital status of the head. Households, families, and subfamilies with a head and his wife present are termed "husband-wife" households, families, or subfamilies. Households, families, and subfamilies with no spouse of head present are termed "other male head" or "female head," depending on the sex of the head.

A married couple is defined as a husband and his wife enumerated as members of the same household. The number of married couples is the sum of the number of husband-wife families and husband- wife subfamilies.

One person in each household is designated as the "head"; the number of heads of households is, therefore, equal to the number of households. The same principle applies to families and subfamilies. The head is generally the person so reported by the household respondent; however, in order to avoid establishing a separate category for the small number of families with the wife reported as the head, such families are edited to show the husband as the head.
Wife of household head, family head, or subfamily head
The number of women who are wives of heads in each category is the same as the number of husband- wife households, husband-wife families, or husband- wife subfamilies. The classification includes women in common-law marriages as well as women in formal marriages.

"Own" children in a household, family, or subfamily comprise the head's sons and daughters, including stepchildren and adopted children, living in the home. The count of own children under 18 years old is limited to single (never married) children; however, "own children under 25" and "own children of any age," as the terms are used here, include all children of the head regardless of marital status.

In a three-generation family, the determination as to whether there are any "own" children of the family head depends on which person in the family is identified as the head. If the family head belongs to the middle generation, his or her children are counted as "own" children of the family head. However, if a member of the oldest generation is reported as the family head, the members of the youngest generation are recorded as grandchildren rather than "own" children of the family head; in such a case the members of the youngest generation and their parents form a subfamily, in which the youngsters (under 18) are classified as "own" children of the subfamily head.

"Related" children, as the term is used in this report, include all family members under 18 except the family head and his wife, regardless of marital status. Thus, the category includes, in addition to "own children," all ever-married children under 18 of the family head and all grandchildren, nephews, cousins, etc., of the family head who were enumerated as members of the household. Related children other than own' children were identified in the coding operation only for those in primary families; such children, however, constitute well over 99 percent of all children in families.

A nonrelative of the head is any member of the household who is not related to the household head. This category includes lodgers (roomers and partners, relatives of such persons, and foster children) and resident employees (maids, hired farm hands, etc.).

Population reports for each census since 1850 contain figures on the number of households, but some of the earlier census figures are limited to the free population and have other limitations. After the 1900 Census had been taken, a few household characteristics for 1790 were tabulated for the free population in those areas with census records still in existence, and the results were reported in chapter VIII of A Century of Population Growth in the United States, 1790-1900, U.S. Government Printing Office, Washington, D.C., 1909. Beginning with 1890, more adequate household data in varying degrees of detail were published.

In 1947, the Bureau of the Census adopted a revised set of Household and family concepts. Statistics on "families" and "private households" in earlier reports are, in general, comparable with statistics on "households" in reports published in 1947 and subsequent years. In the 1960 and 1950 reports, the number of households is equal to the number of primary families plus the number of primary individuals. Primary individuals are persons who would have been classified as "one-person families" under the former terminology. The definition of families adopted in 1947 includes the small number of secondary families which would not have been classified as families under the old definition.

The definition of a household used in 1960 differs slightly from that used in the 1950 Census and in the 1940 Census. The change arises as a result of the shift from a dwelling unit to a housing unit as the basic unit of enumeration in the Census of Housing. According to the 1960 definition, a household consists of all the persons who occupy a housing unit, whereas in the 1950 and 1940 Censuses, a household consisted of all the persons who occupied a dwelling unit.

Table A. Population per Household, For the United States: 1890 to 1960
(Population includes persons not in households. Number of households for 1920, 1910, and 1890 includes quasi-households)

Area and census year

Households

Population per household

United States

1960

53,021,061

3.38

Conterminous United States

1960

52,810,747

3.38

1950

42,857,335

3.52

1940

34,948,666

3.77

1930

29,904,663

4.11

1920

24,351,676

4.34

1910

20,255,555

4.54

1900

15,963,965

4.76

1890

12,690,152

4.93

A dwelling unit was defined as: (1) A group of rooms occupied or intended for occupancy as separate quarters and having either separate cooking equipment or a separate entrance; or (2) a single room (a) if it had separate cooking equipment, (b) if it was located in a regular apartment house, or (c) if it constituted the only living quarters in the structure.

Housing units differ from dwelling units mainly in that separate living quarters consisting of one room with direct access but without cooking equipment always qualify as a housing unit in 1960 but qualified as a dwelling unit before 1960 only when located in a regular apartment house or when the room was the only living quarters in the structure.

The evidence so far available suggests that the change from the dwelling unit concept to the housing unit concept had relatively little effect on the number of households for the Nation as a whole and for large areas. Any effect which the change in concept may have can be expected to be greatest in statistics shown in other reports for some small areas, such as city blocks and census tracts. Living quarters classified as housing units in 1960 but which would not have been classified as dwelling units in the earlier censuses tend to be clustered in neighborhoods where many persons live alone in single rooms in hotels, rooming houses, and other light housekeeping quarters. For the 17 metropolitan areas shown separately in the report on the Components of Inventory Change survey of December 1959, the count of housing units for the combined 17 areas from the (April) 1960 Census is slightly higher than the count of dwelling units from the 1959 survey; this difference exists even after allowing for Sampling Variability of the 1959 estimate and the difference in dates of enumeration.

Furthermore, the estimate from the 1960 Census of the number of 1- and 2-room renter-occupied housing units in the 17 areas is higher than the estimate of dwelling units in the comparable category from the 1959 survey. 1

The count of households in 1950, 1940, 1930, and 1900 excluded groups of persons living as members of quasi-households. However, the numbers for 1920, 1910, and 1850 to 1890 included quasi-households. A quasi- household was defined in 1950 as the occupants of s rooming house containing five or more persons not related to the head, or the occupants of certain other types of living quarters, such as dormitories, military barracks, and institutions. According to the 1940 definition, a rooming house was regarded as a quasi-household only when it included eleven or more persons not related to the head. The concept of quasi- household used in 1950 and 1940 is thus similar to the concept of group quarters used in 1960.

Except for the household concept, the other 1960 definitions relating to household and family composition are essentially the same as those previously used. However, the 1950 data on families include the small number in quasi-households, whereas, in 1960, statistics on families were compiled only for those in households.

Despite the similarity of definitions of household relationship, the national statistics for certain relatively small categories by relationship and family status appear to have been significantly affected through the change in the household definition. The change in household definition introduced in 1960 would theoretically tend to make the numbers of primary families and primary individuals enumerated in 1960 higher than the numbers that would have been obtained under earlier procedures, and to make the numbers of secondary families and secondary individuals lower. The evidence available indicates that, for the Nation as a whole, the number of husband-wife secondary families and the number of males classified as secondary individuals were lower in 1960 than they would have been under the earlier procedures. However, because these numbers are relatively small, even a substantial proportional reduction in them would not necessarily produce a significant increase in the national totals of the much more numerous primary families and primary individuals.

The number of households in the United States according to the 25-percent sample is virtually identical with the number according to the complete count, because the number in the sample was controlled to agree with that in the complete count (table B). This control did not extend, however, to the two types of households (primary families and primary individuals). Thus, the 25-percent sample as published underrepresented primary individuals by about 354,000, or 4 percent, and overrepresented husband-wife primary families by about 393,000, as compared with complete-count data. Moreover, the number of own children under 18 years of age was 1.3 percent larger in the 25-percent sample than in the complete count. Investigation of available data suggests that these differences arose primarily in the Sample Designation. The procedure for selecting the sample would have produced unbiased results if the design had been carried out according to instructions. The designation of the sample by the enumerator at the time he was canvassing was a low-cost procedure, which created some opportunity for undetected errors to occur and made control difficult.

The figures from the 4-percent sample tend to be in very close agreement with those from the 25-percent sample.

Table B. Comparison Of Complete-Count Data And Data From 25-Percent And 5-Percent Samples Of The 1960 Census Of Population And Data From The Current Population Survey, For The United States: 1960
(Numbers in thousands. Percent not shown where less than 0.1)

Subject

1960 Census

Current Population Survey

Complete count

25-percent sample

5-percent sample

Total number

Deviation from 5-percent sample

Total number

Deviation from complete count

Total number

Deviation from complete count

Number

Percent

Number

Percent

Number

Percent

Households

53,021

53,024

3

â¦

53,019

-5

â¦

52,610

-409

-0.8

Primary families

44,670

45,027

357

0.8

45,048

21

â¦

44,856

-192

-0.4

Primary individuals

8,351

7,997

-354

-4.2

7,972

-25

-0.3

7,754

-218

-2.7

Families

(1)

45,128

(1)

(1)

45,149

21

â¦

45,062

-87

-0.2

Husband-wife families

(1)

39,641

(1)

(1)

39,657

16

â¦

39,335

-322

-0.8

Primary families

39,210

39,603

393

1.0

39,618

15

â¦

39,260

-358

-0.9

Subfamilies

(1)

1,424

(1)

(1)

1,428

4

0.3

1,511

83

5.8

Own children under 18 in families

259,582

60,347

765

1.3

59,877

-470

-0.8

59,833

-44

-0.1

1 Not available.2In primary families.

Comparisons of figures from the present report on the number of own or related, children under 18 years old of the family head with corresponding figures from certain other 1960 Census reports may be affected by the fact that the child's own sample inflation weight was invariably used in the present report, whereas the parent's sample inflation weight was used in other reports. Some of the tables in chapter D of Volume I, such as table l8l in the United States Summary, contain data on children under 18 that are weighted like those in table 6 of the present report, whereas other tables in chapter D, such as table 185 in the United States Summary, contain data on children based on the head's weight.

Table B includes comparisons of figures from the Current Population Survey (CPS) with those from the present report, which are based on the 1960 Census J-percent sample. Most of the key statistics in the CPS with regard to the numbers of households and families agree closely with those in the 5-percent sample. Thus, the numbers of families, subfamilies, primary individuals, and own children under 18 in the CPS and corresponding numbers in the 5-percent sample are within the limits of sampling error at the two-standard-error level (as measured from the CPS). The number of primary individuals in the CPS is 7 percent below the complete-count number in the census. The differences between census and CPS residence rules may be in part responsible for this result; in the census, students are counted in the community where they attend college (and where some of them maintain an apartment), but in the CPS, unmarried students are counted as residents of their parental homes.

The median is presented in connection with the data on income. It is the value which divides the distribution into two equal parts, one-half the cases falling below this value and one-half the cases exceeding this value. A plus (+) or minus (-) after the median indicates that the median is above or below that number. For example, a median of $10,000+ for income indicates that the median fell in the interval "$10,000 or more."

The average or mean is presented in connection with data on number of children in the family, size of family, Years of School Completed, and family income. For instance, the mean size of family is obtained by dividing the total number of members in families by the number of families.

In general, the urban population comprises all persons living in Urbanized Areas and in places of 2,500 inhabitants or more outside Urbanized Areas. More specifically, according to the definition adopted for use in the 1960 Census, the urban, population comprises all persons living in (a) places of 2,500 inhabitants or more incorporated as cities, boroughs, villages, and towns (except towns in New England, New York, and Wisconsin); (b) the densely settled urban fringe, whether incorporated or unincorporated, of Urbanized Areas; (c) towns in New England and townships in New Jersey and Pennsylvania which contain no incorporated municipalities as subdivisions and have either 25,000 inhabitants or more or a population of 2,500 to 25,000 and a density of 1,500 persons or more per square mile; (d) counties in States other than the New England States, New Jersey, and Pennsylvania that have no incorporated municipalities within their boundaries and have a density of 1,500 persons or more per square mile; and (e) unincorporated places of 2,500 inhabitants or more. The population not classified as urban constitutes the rural population.

The rural population is subdivided into the rural-farm population, which comprises all rural residents living on farms, and the rural-nonfarm population, which comprises the remaining rural population. The nonfarm population, as the term is used in this report, comprises persons living in urban areas and rural persons not on farms. In the 1960 Census, the farm population consists of persons living in rural territory on places of 10 or more acres from which sales of farm products amounted to $50 or more in 1959 or on places of less than 10 acres from which sales of farm products amounted to $250 or more in 1959.

An urbanized area contains at least one city of 50,000 inhabitants or more in 1960 and the surrounding closely settled incorporated places and unincorporated areas that meet certain criteria relating to population density or land use. An urbanized area may be thought of as divided into the central city, or cities, and the remainder of the area, or the urban fringe. All persons residing in an urbanized area are included in the urban population.

Except in New England, an SMSA is a county or group of contiguous counties which contains at least one city of 50,000 inhabitants or more, or "twin cities" with a combined population of at least 50,000. In addition to the county, or counties, containing such a city or cities, contiguous counties are included in an SMSA if, according to certain criteria, they are essentially metropolitan in character and are socially and economically integrated with the central city. In New England, SMSA's consist of towns and cities, rather than counties.

The population inside SMSA's is further classified as "in central city" and "in ring" (outside central cities). With a few exceptions, central cities are determined according to the following criteria:
1. The largest city in an SMSA is always a central city.
2. One or two additional cities may be secondary central cities on the basis and in the order of the following criteria:
a. The additional city or cities have at least 250,000 inhabitants.
b. The additional city or cities have a population of one-third or more of that of the largest city and a minimum population of 25,000.

The term "color" refers to the division of population into two groups, white and nonwhite. The color group designated as "nonwhite" consists of such races as the Negro, American Indian, Japanese, Chinese, Filipino, Korean, Hawaiian, Asian Indian, Eskimo, Aleut, and Malayan races. Persons of Mexican birth or ancestry who are not definitely of Indian or other nonwhite race are classified as white.

In addition to persons of Negro and of mixed Negro and white descent, this classification includes persons of mixed Indian and Negro descent, unless the Indian ancestry predominates or unless the individual is regarded as an Indian in the community.

In addition to full-blooded Indians, persons of mixed white and Indian blood are included if the proportion of Indian blood is one-fourth or more, or if they are regarded as Indian in the community. Indians living in Indian territory or on reservations were not included in the population until 1890.

Persons of mixed racial parentage are classified according to the race of the nonwhite parent, and mixtures of nonwhite races are classified according to the race of the father, with the special exceptions noted above.

This category comprises persons born in the United States, the Commonwealth of Puerto Rico, or a possession of the United States; persons born in a foreign country or at sea who have at least one native American parent; and persons whose place of birth was not reported and whose census report contained no contradictory information, such as an entry of a language spoken prior to coming to the United States.

Persons of foreign stock are classified according to their country of origin-country of birth for the foreign born and parents country of birth for the native of foreign or mixed parentage. Natives of foreign parentage whose parents were born in different countries are classified according to the country of birth of the father. Natives of mixed parentage are classified according to the country of birth of the foreign- born parent. The classification by country of origin is based on international boundaries as recognized by the United States Government on April 1, 1960, although there may have been some deviation from the rules where respondents were unaware of changes in boundaries or jurisdiction.

In table 59, the classification of family heads and their wives by country of origin is based on individual countries or on combinations of several countries that represent a relatively homogeneous ethnic stock. Husbands and wives are classified as being of the same foreign stock when they have the same country of origin or have countries of origin that are included in the same combination of countries. The countries and the combinations used are listed below:

In order to obtain data on Spanish- and Mexican- Americans for areas of the United States where most of them live, white persons (and white heads of families) of Spanish surname were distinguished separately in five Southwestern States (Arizona, California, Colorado, New Mexico, and Texas) during the processing operations. Puerto Ricans comprise persons born in Puerto Rico and persons born in the United States or its possessions with one or both parents born in Puerto Rico.

Residence on April 1, 1955, is the usual place of residence five years prior to enumeration. The category "same house as in 1960" includes all persons 5 years old and over who were reported as living in the same house on the date of enumeration in 1960 and five years prior to enumeration. Included in the group are persons who had never moved during the five years as well as those who had moved but by 1960 had returned to their 1955 residence. The category "different house in the U.S." includes persons who, on April 1, 1955, lived in the United States in a different house from the one they occupied on April 1, 1960. This category was subdivided into four groups according to their 1955 residence, viz., "different house, same county," "different county, same State," "contiguous State," and "noncontiguous State." States are classified as contiguous if their boundaries touch at any point. A list of the contiguous States for each State is given in report PC(2)-2A, State of Birth. The category "abroad" includes those with residence in a foreign country or an outlying area of the United States in 1955. (In the coding of this item, persons who lived in Alaska or Hawaii in 1955 but in other States in 1960 were classified as living in a noncontiguous State in 1955.) Persons 5 years old and over who had indicated they had moved into their' present residence after April 1, 1955, but for whom sufficiently complete and consistent information regarding residence on April 1, 1955, was not collected are included in the group "moved, place of Residence In 1955 not reported."

In table 57, a family was classified as having all members in the same mobility status if all members 5 years old and over were classified in the same one of the following ten categories:

In SMSA in 1960:
1. Same house in 1955
2. Different house in central city of this SMSA in 1955
3. Different house in ring of this SMSA in 1955
4. Central city of different SMSA in 1955
5. Ring of different SMSA in 1955
6. Not in SMSA in 1955

Not in SMSA in 1960:
7. Same house in 1955
8. In central city of SMSA in 1955
9. In ring of SMSA in 1955
10. Different house not in SMSA in 1955

In preparing the record for the 5-percent sample, on which the present report is based, all movers from one borough to another within New York City were classified as movers within the "same county," whereas In reports, based on the 25-percent record, persons who moved across borough lines were classified as movers between counties within the "same State." Hence, the 5-percent sample shows more family heads who were movers within the same county than would be shown in corresponding figures from the 25-percent sample, and fewer migrants between counties within the same State. This difference should have little influence on the percent distributions by characteristics of families in the various mobility status classes.

School Enrollment is shown for persons 5 to 34 years old. Persons were included as enrolled in school if they were reported as attending or enrolled in a "regular" school or college at any time between February 1, 1960, and the time of enumeration. Regular schooling is that which may advance a person toward an elementary school certificate or high school diploma, or a college, university, or professional degree. Schooling that was not obtained in a regular school and schooling from a tutor or through correspondence courses were counted only if the credits obtained were regarded as transferable to a school in the regular school system. Schooling which is generally regarded as not regular includes that which is given in nursery schools, in specialized vocational, trade, or business schools; in on-the-job training; and through correspondence courses.

Elementary school, as defined here, includes grades 1 to 8, and high school includes grades 9 to 12. College includes junior or community colleges, regular 4-year colleges, and graduate or professional schools. In general, a "public" school is defined as any school which is controlled and supported primarily by a local, State, or Federal agency. All other schools are "private" schools.

"Undergraduate" college students are those enrolled in one of the first four academic years of college. "Graduate school" students, as the term is used here, refers to persons enrolled in the fifth year of college or beyond.

Children 5 to 17 years of age are classified as being below, at, or above the modal (most common) grade level for their age by comparison of their grade with the following modal values:

age

Modal level for grade in which enrolled

Modal level for highest grade completed

5

Never attended 1st grade

â¦

6

Never attended 1st grade and attended 1st grade

0

7

1st and 2nd grades

0 an 1st grade

8

2nd and 3rd grades

1st and 2nd grades

9

3rd and 4th grades

2nd and 3rd grades

*

*

*

*

*

*

*

*

*

17

3rd and 4th year high school

2nd and 3rd year high school

In table 28, the data on enrolled children are limited to those under 18 years old who were enrolled in elementary school or in high school.

The data on Years of School Completed (also termed "education" and "educational attainment" in this report) were derived from the answers to the two questions: (a) "What is the highest grade (or year) of regular school he has ever attended?" and (b) "Did he finish this grade (or year)?" Enumerators were instructed to obtain the approximate equivalent grade in the American school system for persons whose highest grade of attendance was in a foreign school system, whose highest level of attendance was in an ungraded school, whose highest level of schooling was measured by "readers," or whose training by a tutor was regarded as qualifying under the "regular" school definition. Persons were to answer "No" to the second question if they were attending school, had completed only part of a grade before they dropped out, or failed to pass the last grade attended.

The number in each category of highest grade of school completed represents the combination of (a) persons who reported that they had attended the indicated grade and finished it, and (b) those who had attended the next higher grade but had not finished it.

As used in the present report, the category "high school graduate" comprises persons who completed 4 years of high school or beyond. The category "college graduate" comprises persons who completed 4 or more years of college.

Persons classified as having no college education (in table 25) or no high school education (in table 26) include some persons who started but did not complete the first year of college or high school, respectively.

This classification refers to the marital status of the person at the time of enumeration. Persons classified as "married" comprise, therefore, both those who have been married only once and those who remarried after having been widowed or divorced. Persons reported as separated (either legally separated or otherwise absent from the spouse because of marital discord) are classified as a subcategory of married persons with spouse absent. The enumerators were instructed to report persons in common-law marriages as married and persons whose only marriage had been annulled as single. Persons "ever married" are those in the categories married (including separated), widowed, and divorced.

A married person with "spouse present" is a man or woman whose spouse was enumerated as a member of the same household even though he or she may have been temporarily absent on business or vacation, visiting, in a hospital, etc., at the time of enumeration. Persons classified as "married, spouse absent" include both those who are separated and those with spouse absent for other reasons.

Whether or not the person was married more than once was determined without regard to the person's marital status at the time of the enumeration.

Year of First Marriage, Years since First Marriage, and Age at First Marriage

In the 1960 Census, persons in the 25-percent sample who had ever been married were asked the date of their first marriage; this information was tabulated in terms of year or calendar quarter and year. Thus, direct information was obtained for this report on year of first marriage for married (including separated), widowed, and divorced persons.

The number of years since first marriage was derived by subtraction of the date of first marriage from April 1, 1960, and represents the interval in completed years since first marriage.

age at first marriage was derived from date (calendar quarter and year) of birth and date of first marriage and represents age in completed years at first marriage.

The data on Employment Status relate to the calendar week prior to the date on which the respondents filled their Household Questionnaires or were interviewed by enumerators. This week is not the same for all respondents because not all persons were enumerated during the same week.

Employed persons comprise all civilians 14 years old and over who were either (a) "at work"-those who did any work for pay or profit, or worked without pay for 15 hours or more on a family farm or in a family business; or (b) were "with a job but not at work"- those who did not work and were not looking for work but had a job or business from which they were temporarily absent because of bad weather, industrial dispute, vacation, illness, or other personal reasons. In tables 38 to 43, members of the Armed Forces are also classified as employed, in the sub-classification for "worked less than 35 hours."

Persons are classified as unemployed if they were years old and over and not "at work" but looking for work. A person is considered as looking for work not only if he actually tried to find work but also if he had made such efforts recently (i.e., within the past 60 days) and was awaiting the results of these efforts. Persons waiting to be called back to a job from which they had been laid off or furloughed are also counted as unemployed.

The "civilian labor force", includes all persons classified as employed or unemployed, as described above. The "labor force" also includes members of the Armed Forces (persons on active duty with the United States Army, Air Force, Navy, Marine Corps, or Coast Guard).

Persons "not in the labor force" comprise all those 14 years old and over who are not classified as members of the labor force, including persons doing only incidental unpaid family work (less than 15 hours during the week).

The statistics on Hours Worked pertain to the number of hours actually worked, and not necessarily to the number usually worked or the scheduled number of hours. For persons working at more than one job, the figures reflect the combined number of Hours Worked at all jobs during the week preceding the date of enumeration. The data on Hours Worked presented in this report provide a broad classification of persons at work into full-time and part-time workers. Persons are considered to be working full time if they worked 35 hours or more during the reference week and part time if they worked less than 35 hours. In tables 38 and 39, the category "head worked less than 35 hours" includes employed heads who did not work during the week preceding the date of enumeration, and members of the Armed Forces.

The data on weeks worked in 1959 pertain to the number of different weeks during 1959 in which a person did any work for pay or profit (including paid vacation and sick leave) or worked without pay on a family farm or in a family business. Weeks of active service in the Armed Forces are also included.

The "Year Last Worked" pertains to the most recent year in which a person did any work for pay or profit, or worked without pay on a family farm or in a family business. Active service in the Armed Forces is also included. Data derived from this item were tabulated for persons classified as not in the labor force and for persons classified as unemployed. Persons not in the labor force with work experience within the last 10 years are referred to as members of the "labor reserve."

Some of the data on occupation in this report are for employed persons and refer to the job held during the week for which employment status was reported. For persons employed at two or more jobs, the data refer to the job at which the person worked the greatest number of hours. Other data are for persons with work experience and relate either to the present job or to the last job held since 1950.

In this report, the category "with work experience" includes persons in the labor force who have ever worked and persons not in the labor force who have worked at any time since 1950. The occupation statistics presented here are based on the detailed system developed for the 1960 Census; see 1960 Census of Population, Classified Index of Occupations and Industries, U.S. Government Printing Office, Washington, D.C., 1960.

Means of Transportation to Work refers to the principal mode of travel or type of conveyance used in traveling to and from work by civilians at work during the reference week and Armed Forces personnel (except those on leave, sick, etc.), In this report, persons are classified as "using auto as principal Means of Transportation to Work" if they reported that they traveled to and from work by private automobile, or carpool.

Information on income for the calendar year 1959 was requested from all persons 14 years old and over in the sample. "Total income" is the sum of amounts reported separately for wage or salary income, self-employment income, and other income. Wage or salary income is defined as the total money earnings received for work performed as an employee. It represents the amount received before deductions for personal income taxes, Social Security, bond purchases, union dues, etc. Self-employment income is defined as net money income (gross receipts minus operating expenses) from a business, farm, or professional enterprise in which the person was engaged on his own account. Other income includes money income received from such sources as net rents, interest, dividends, Social Security benefits, pensions, veterans' payments, unemployment insurance, and public assistance or other governmental payments, and periodic receipts from insurance policies or annuities. Not included as income are money received from the sale of property (unless the recipient was engaged in the business of selling such property), the value of income "in kind," withdrawals of bank deposits, money borrowed, tax refunds, and gifts and lump-sum inheritances or insurance payments.

"Earnings" comprise wage or salary and self-employment Income, but exclude other income. "Income recipients" are persons who received income from any source as defined above. The chief income recipient in a family was defined, in general, as that member of a family who had the largest total income (at least $1 more than any other family member).

In the statistics on family Income, the combined incomes of all members of each family are treated as a single amount. Although the time period covered by the Income statistics is the calendar year 1959, the composition of families refers to the time of enumeration. For most of the families, however, the income reported was received by persons who were members of the family throughout 1959.

A housing unit is "owner occupied" if the owner or co-owner lives in the unit, even if it is mortgaged or not fully paid for. The head himself need not be the owner. All other occupied units are classified as "renter occupied," whether or not cash rent is paid. Examples of units for which no cash rent is paid include units occupied in exchange for services rendered, units owned by relatives and occupied without payment of rent, and units occupied by sharecroppers. Primary families are classified as "owner primary families" and "renter primary families" according to the tenure of the housing unit.

The number of persons per room was computed for each housing unit by dividing the total number of household members by the number of rooms in the unit. The number of rooms is the count of whole rooms used for living purposes, such as living rooms, dining rooms, bedrooms, kitchens, finished attic or basement rooms, recreation rooms, lodgers' rooms, and rooms used for offices by a person living in the unit. Not counted as rooms are bathrooms; halls, foyers, or vestibules; closets; alcoves; pantries; strip or pullman kitchens; laundry or furnace rooms; unfinished attics, basements, and other space used for storage.

In determining the number of units in the structure, the enumerator was instructed to count both occupied and vacant housing units but not to count business units or group quarters. A structure is defined as a separate building that either has open space on all four sides, or is separated from other structures by dividing walls that extend from ground to roof.

Living quarters are regarded as having direct access if the entrance is direct from the outside of the structure, or through a common hall, lobby, or vestibule used by the occupants of more than one unit. The hall, lobby, or vestibule must not be part of any unit, but must be clearly separate from all units in the structure. Living quarters do not have direct access when the only entrance to the room or rooms is through a room or hall which is part of another unit.

A kitchen is defined as a room used primarily for cooking and the preparation of meals. Cooking equipment is defined as (1) a range or stove, whether or not it is regularly used, or (2) other equipment such as a hotplate or electrical appliance if it is used for the regular preparation of meals. The category "with kitchen or cooking equipment" comprises units with facilities for exclusive use; the category "lacking kitchen or cooking equipment" comprises units with shared or no facilities. Equipment is for exclusive use if it is used only by the occupants of one unit.

The enumerator determined the condition of the housing unit by observation, on the basis of specified criteria related to the extent or degree of visible defects. Although detailed oral and written instructions and visual aids were provided, the application of the criteria involved some judgment on the part of the individual enumerator. The training program for enumerators was designed to minimize differences in judgment.

Sound housing is defined as that which has no defects, or only slight defects which are normally corrected during the course of regular maintenance. Deteriorating housing needs more repair than would be provided in the course of regular maintenance. Such housing has one or more defects of an intermediate nature that must be corrected if the unit is to continue to provide safe and adequate shelter. In some tables, "sound" and "deteriorating" are combined into one category, "not dilapidated."

Dilapidated housing does not provide safe and adequate shelter and in its present condition endangers the health, safety, or well-being of the occupants. Such housing has one or more critical defects, or has a combination of intermediate defects in sufficient number or extent to require considerable repair or rebuilding, or is of inadequate original construction. Critical defects result from continued neglect or lack of repair, or indicate serious damage to the structure.

A housing unit, with a flush toilet inside the structure and available to the occupants of the unit is classified according to whether it is for exclusive use or is shared with occupants of other units.

A housing unit has "hot piped water" if there is running water inside the structure and it is available to the occupants of the unit. A unit has piped hot water even though the hot water is not supplied continuously; for example, it may be supplied only at certain times of the day, week, or year.

A clothes washing machine owned by a member of the household was to be reported, whether it was located in the housing unit or elsewhere on the property. Machines used but not owned by members of the household, such as those provided by the management of an apartment building, were not to be reported. The number of households with a washer and a dryer (or a washer-dryer combination) are shown in some of the tables. Dryers used but not owned by members of the household, such as those provided by the management of an apartment building, were not to be reported.

A home food freezer is defined as an appliance, separate from the refrigerator, which freezes food and keeps food frozen. The freezer must be located in the housing unit or elsewhere on the property. Excluded is a freezer combined in the same cabinet with a refrigerator, even if it has a separate door.

A unit is classified as having a telephone if there is a telephone available to the occupants of the unit for receiving calls. The telephone may be located inside or outside the housing unit, and one telephone may serve the occupants of several units.

The count of automobiles available represents the number of passenger automobiles, including station wagons, owned or regularly used by any of the occupants of the housing unit. Passenger cars were to be counted if they were owned by a member of the household or if they were regularly used and ordinarily kept at home, such as some company cars. Not to be counted were taxis, pickups or larger trucks, and dismantled or dilapidated cars in an early stage of being junked. The statistics do not reflect, the number of automobiles privately owned or the number of households owning one or more automobiles.

Air conditioning is defined as the cooling of air by refrigerating apparatus. Excluded are evaporative coolers and fans or blowers which are not connected to a refrigerating apparatus. Separate statistics are shown in table 32 for primary families having air conditioners designed to cool one room and for those designed to cool more than one room (including central systems). A central system is an installation which air-conditions a number of rooms. In an apartment building, a central system usually provides air conditioning for all the apartments.

Television sets of all kinds located in the unit were to be included in the count-floor, table, built-in, portable, and combination with radio or phonograph. Sets in working order and sets being repaired were to be counted. A combination radio-television .set was' to be reported both as a television and as a radio set.

Value is the respondent's estimate of how much the property would sell for on the current market (April 1960). Value data are restricted to owner- occupied units having only one housing unit in the property and no business. Units in multiunit structures and trailers were excluded from the tabulations; and, in rural territory, units on farms and all units on places of 10 acres or more (whether farm or nonfarm) also were excluded.

Gross rent is shown as a percent of family income, for nonfarm primary families. Renter households not paying any rent for the housing unit are classified in the category "gross rent under 20 percent of income." Gross rent is based on the information reported for contract rent and the cost of utilities and fuel. Contract rent is the monthly rent agreed upon regardless of any furnishings, utilities, or services that may be included. The computed rent termed "gross rent" is the contract rent plus the average monthly cost of utilities (water, electricity, gas) and fuels such as wood, coal, and oil if these items are paid for by the renter. Thus, gross rent eliminates differentials which result from varying practices with respect to the inclusion of utilities and fuel as part of the rental payment. Bent data exclude rents for units in rural-farm territory.